Hi mate, yeah your right, ive just taken the step to upgrade my van to 2 pump settup. I was working off 1 pump split after the resin vessel, but was finding that we were not both getting enough water to rinse properly. I now have 2 pumps with 2 digi controllers, both with their own resin vessels. It was well worth the money, as we both have the controllers turned right down, the pumps dont have to work hard and i dont think water usage is much different (maybe 50l more per day). We now both have the water we need to rinse properly, we noticed the difference within the first few houses!!